“Every insect has its proper plant, or tribe of plants, which it naturally requires for its nourishment, and on which it generally lays its eggs, and that on the most concealed parts of the plant; and the plant, and insect which attacks it, are always natives of the same climate, and therefore endure the same degrees of heat and cold; consequently, when plants are attacked by their natural tribe of insects, it is an exceedingly nice and curious operation to exterminate them without injuring the plants, or stopping them in their natural growth. But observing that insects increase rapidly in hot dry weather, and that they appear impatient of moisture, was the means of inducing me try which would bear the greatest heat and live.” “To ascertain what degree of heat a Pine Apple plant can endure without destroying it, I filled four vessels with hot water. The water in the first vessel was 130 degrees hot; that in the second 140; that in the third 145; that in the fourth 150. Into each of these vessels I put a few Pine plants, divested of their roots, of their fibrous roots, and suffered them to remain in the water about an hour. The plants which had been immersed in the water heated to 140 and 145 degrees, were a little hurt in the extremities of their leaves, but after being dried in the hot-house, they were planted, and grew as vigorous as if they had not been put into hot water; the plants put into water 130 degrees warm were not in the least injured; but those put into water heated to 150 degrees were entirely destroyed. “By this experiment I ascertained that a vegetable can endure, without hurting it, 130 degrees of heat, according to the degrees on Fahrenheit’s thermometer. I am inclined to think that no animal is able to endure such a heat and live. Undoubtedly, insects increase rapidly in hot weather in the open air, especially on the peach tree, and on other trees, against warm walls, both in the spring and summer months; and they increase most rapidly in dry weather; but the heat in the open air against walls seldom rises to 100 degrees. And in the hottest countries in the world, where vegetables and animals exist, the heat in the shade seldom rises to blood heat, which is about 97. Having considered these things, and ascertained that a plant can endure a heat of 130 degrees, I determined to try another experiment, that is, to ascertain whether heat and water would destroy insects, and keep plants alive. I therefore thought of, and determined to try, the following method: